1. Department of Otorhinolaryngology-Head and Neck Surgery; Seoul National University Hospital; Seoul Korea
2. Department of Otorhinolaryngology-Head and Neck Surgery; Kangnam Sacred Heart Hospital; Seoul Korea
3. Department of Otorhinolaryngology-Head and Neck Surgery; Seoul National University Bundang Hospital; Seongnam Korea
4. Department of Otorhinolaryngology-Head and Neck Surgery; Seoul National University Boramae Medical Center; Seoul Korea
5. Department of Otorhinolaryngology-Head and Neck Surgery; Asan Medical Center; Seoul Korea
6. Department of Otorhinolaryngology-Head and Neck Surgery; Samsung Medical Center; Seoul Korea
7. Department of Otorhinolaryngology-Head and Neck Surgery; Seoul St. Mary's Hospital; Seoul Korea
8. Department of Otorhinolaryngology-Head and Neck Surgery; Korea University Ansan Hospital; Ansan Korea
9. Department of Otorhinolaryngology-Head and Neck Surgery; Konkuk University Hospital; Seoul Korea
10. Department of Otorhinolaryngology-Head and Neck Surgery; Dankook University Hospital; Cheonan Korea
11. Department of Otorhinolaryngology-Head and Neck Surgery; Chungnam National University Hospital; Daejeon Korea
12. Department of Otorhinolaryngology-Head and Neck Surgery; Gyeongsang National University Hospital; Jinju Korea
13. Department of Otorhinolaryngology-Head and Neck Surgery; Kyungpook National University Hospital; Daegu Korea
14. Department of Otorhinolaryngology-Head and Neck Surgery; Chonbuk National University Hospital; Jeonju Korea
15. Department of Otorhinolaryngology-Head and Neck Surgery; Chonnam National University Hwasun Hospital; Gwangju Korea
16. Department of Otorhinolaryngology-Head and Neck Surgery; Pusan National University Yangsan Hospital; Yangsan Korea